Hoisting mechanism.



' E REID. HOISTING MECHANISM. APPLIUATION FILED APR.2,19Q6.

Patented Dec. 15, 1908.

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m. Z Z 5. WWW 0 f i .J a. 2 2 3% m E. S. REID. HOISTING MECHANISM. APPLICATION FILED APR.2,1906.

Patented Dec; 15, 1908.

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UNI.-

' gil h i ile EDWARD S. REID, OF DETROIT, MICHIGAN, ASSIGNOR TO NORTHERN ENGINEERING WORKS,

. OF DETROIT, MICHIGAN, A CORPORATION OFMlCl-HGAN.

I HOISTING MECHANISM.

hlo. soccer.

To'ijtllwhcm e3 concern:

Be it lmowh that l EDWARD 8. Ram, a citiseu' of the "United cltates oi America, residin at Detroit, in the county of Wayne and tats of Michigan, have invented certain new and useful improvements in Hoisting Mechanism of which the following is a speci fication, rerereuce being had therein to the accompanying drawings.

- The inventwn has reference generally to hoisting mechanism having means for arresting movement of the load at any predetermiued point, and it cchsists primaril in the association with mechanism or this 0 aracter hf a signal adapted to operate prior to the operation of the arresting insane. The invention further consists in the peculiar arrangement and combination of the various parts of the mechanism, and invarious details of construction as more fully hereinafter described and claimed. The si al is applicable to any form of raismg end owering mechanism, and may operate upocd the lifting of the load or upon its lowering movement, as desired.

For the urpose of illustration, 1 have shown and escribeda signal as used in connection with an ordinary travelmgyrane providedufith an automatic cutout switch for stoppmgthe load in proximity ti) the load bloc in order to prevent damage to the mach nery, the signs. being designed to operate prior to the automatic actuation of the switch, so that the latter will not operate an d will not lie-required to be reset.

.In the drawmgs,-Figure 1 is a side elevat on of a crane, partly broken away, with the signal applied Fig- 2 is an end elevation, illustrating the hoistin drum and signal; and Fig. 3 is a diagram s owing the preferred system of wiring ior an electric signal associated with an e crane.

a A represents an electrically operated crane, provided with wheels a, which travel on tracks a.

A is the usual controller on the operating platform A The crane A is provided with tracks I), on which travel a hoisting and lowering mech amsm proper a having the usual wheel 1) ruumng on the tracks I). The hoisting mechamsm comprises a frame B, a motor b, a Wmdmg drum TR. together with drive incohamsm and other essential parts not herein ectrically operated hoist or $peciflcation of Letters Patent.

Patented Dec. 15, 1908.

hp licstlon riled April 2, 1906. Serlal No. 309,533.

shown, as they form no part of the present invention.

C is the usual load block, carrying the hook C, su ported by a suitable cable 0 wound upon t 1e drum in the usual manner.

The arresting means for stopping the load at a predetermined point is oi he following construction D is an extension of the drum shaft projectin through the frame B and externally three ed, as shown.

d is a. cap on the end of the extension.

U on the threaded ortion of the shaft depen s an arm or nut interiorly threaded to engage the shaft thread, the direction of the thread being such that on the operation of hoisting, the arm remaining in a depending position,due to gravity-it will be carrie inwardly eventually into contact with the shoulder d on the shaft extension.

C re resents a safety switch secured to the frame on one side of the shaft extension and included in the motor circuit in the usual manner and well known to those skilled in the art. It is adapted to be operated by a spring D on the side of the depending arm E as said arm rotates.

The signal may be of any suitable constructiou, but it is herein shown as including in its construction a spring F on the side of the arm toward the frame B, and in its path andlocated on the frame is a push button F adapted to be operated by the spring upon the mward movement oi the arm. The push buttoo or switch is included in an electric circuit C", in which is also included a bell (l, referably mounted upon the frame B, the ell in this instance constituting the signal or alarm proper.

It will be obvious that in place of the bell a lamp N or other form of signal may be used,

or ii preferred both the lamp and the bell, it being imumtcrial wheth or the signal is of the audible or visual type. Also, the signal may be 0 erated mechanically, ormaylbe providec with an independent electric circuit with a battery, or in case of its use with an controller. The bell G and the ush button F are included in-a branch circuit around the fiel d. This circuit 'also includes the lamp N, which is preferably used for its resistance,

but may, as previously stated, be omitted if desired.

In the operation ,of the mechanism, the depending nu't or arm E is normally at the outer end of the shaft extension. As the winding drum operates to elevate the load, the arm E travel-s inward toward the frame B. When the load is in proximity to the drum, the spring F engages the'push button and sounds t re alarm or flashes the light, or both, thus indicating to the operator that the danger point is reached and permitting time to reverse and shut olf the current so as to prevent further hoisting. The alarm or signal continues to operate through the spring arm F until the lug d on the depending arm E strikes the shoulder d on the extension D. Upon engagement of the parts (1 and d the arm is rotated with the shaft, causing the spring 1) to strike the switch 0, thus breaking the circuit and reventing further operation of hoisting. hrough the signal, the automatic cutout switch may be prevented from operating and the necessity of the operator resetting the same obviated.

I have here shown for the purpose of illus tration one particular form of apparatus, but it will be obvious that other forms of mechanism can be used and my signal applied wherein the latter will 0 erate before the arresting mechanism, and i do not desire to be limited tovthe specific form of hoisting mechanism herein shown.

What I claim is,

1. In a hoisting mechanism,- the combination with means for raising and lowering the load, of means for arresting the movement of the load at a predetermined point,

anism for raising and lowering the load, of

a signal, means controlled by the raising and. lowering mechanism for automatically operating the signal upon the approach of the load to a predetermined point, and means also controlled by the raising and lowering mechanism for automatically stopping the load upon its arrival at said point.

4. In a hoist the combination with a hoisting drum, of a shaft therefor, a load block, a si nal, means controlled by the rotation of the shaft for automatically stopping the load at a redetermined point, and means also control edby the rotation of the shaft for automatiealloperating the signal upon the near approach of the load-to said point. p

5. In a hoist, the combinationv with a hoisting drum, of a shaft therefor having a threaded extension, a load block, a depending weighted arm threaded on said extension, means automatically operated by said arm for arresting the load at a predetermined point, and a signal also adapted to be operated by said arm upon the near approach of the load to saidpoint.

In testimony whereof I aliix my signature in presence of two witnesses.

EDWARD S. REID.

Witnesses:

JAMES P. BARRY, EDWARD S. GULF. 

